Rocket nozzles have a bell shape to take advantage of the effects of a DeLaval nozzle (which I'm sure you're aware of). There is a world of difference between rocket exhaust and the muzzle blast from a pneumatic.

With a larger barrel, velocity would be less, mass of the expanding air the same, less recoil. If you care to throw some numbers at it, I'll even get you started:

EDIT: Plugging in numbers for this build gives me only 185m/s exhaust velocity, actually less than SOS, which we normally assume in recoil calculations.

It was taken away from me on a noise complaint. The guy cited some township ordinance.
(That should give you an idea of how loud it was - I live on a 40 acre farm away from everyone)

There's a good chance that it'll be given back to me. I kinda cheated them anyway.. I knew they were coming so I took off the valves and all the valuable stuff. They took the trailer, tank, and barrel. I still have the compressor, valves, hydraulics, and controls.

Hopefully I can resolve it with the "neighbor" and not get the township involved. My other neighbor didn't mind at all...

It's ridiculous that you get your cannon confiscated when you live on a 40 acre farm in America and I live in an affluent suburb in the city with 10 houses within 30m of mine, some of which have young children, and I've never had a complaint.

I probably should refrain from firing my larger cannons at home in the future, considering I can face jail time.

Jimmy K wrote:It was taken away from me on a noise complaint. The guy cited some township ordinance.

Sounds to me like they're jerking you around. If a person drove through town with a defective car muffler, would they confiscate the car? Hell NO......they'd issue a warning or maybe a ticket for violating the noise level ordinance but....they surely wouldn't confiscate it!

Hello everyone. It's been a few months since my big cannon was confiscated and since my last visit to this site. I apologize for not returning to answer questions in due time.

Unfortunately, I have since sold my cannon trailer and some other supplies, but I have drawn up plans for some cool stuff to build this summer.

A smaller version of this cannon is in the works. The barrel has been halved - to 10' - and the sprinkler valves are now pilot valves. 4" piston valve, here I come.

With the smaller barrel size, less supports will be needed, so I will attempt to do 180 degree horizontal movement and 90 degree barrel angle movement like my original plans.

Another exciting prospect is a rifled barrel. I've made some great connections at the University of Alabama and we've been throwing around ideas about rifling a snug bore softball cannon. We think we can work something out.

Also I'm working on founding a group I call Crimson Cannoneers - a university sponsored student group working on ballistics, cannons, etc. With lots of money from dues and the university, some really cool things can be cranked out of this club.

Stay tuned for some cool non-cannon related projects too. I'm currently building a sweet turbojet powered go-cart and some random things.

Also I'm working on founding a group I call Crimson Cannoneers - a university sponsored student group working on ballistics, cannons, etc. With lots of money from dues and the university, some really cool things can be cranked out of this club.

May I be part of that? I'm good at it!! lol, and I have my mauler cannon finished, I just have to wait for my mauler repairs to be finished.. so in about a week or two, I will be shooting golfballs upwards of 600 FPS.

Jimmy K wrote:It was taken away from me on a noise complaint. The guy cited some township ordinance.

Sounds to me like they're jerking you around. If a person drove through town with a defective car muffler, would they confiscate the car? Hell NO......they'd issue a warning or maybe a ticket for violating the noise level ordinance but....they surely wouldn't confiscate it!

Local noise ordinances don't apply to a car's exhaust note in most states. As long as your car complies to state and federal laws concerning emissions, and whatever STATE vehicle-noise laws you might have, your town can't say a thing about it. Stereos and other noise-makers that don't have to do with the drivetrain are a different matter.

Here in Ohio, as long as you have a muffler, it's legal, with the exception of "glasspack" type aftermarket mufflers, which are banned from street use in Ohio.